Editing Off-axis optical system

An '''off-axis optical system''' is an [[optics|optical]] system in which the [[optical axis]] of the [[aperture]] is not coincident with the mechanical center of the aperture. The principal applications of off-axis optical systems are to avoid obstruction of the primary aperture by secondary optical elements, instrument packages, or sensors, and to provide ready access to instrument packages or sensors at the focus. The engineering tradeoff of an off-axis optical system is an increase in image aberrations.

There are various theoretical models for aberration in off-axis optical systems.<ref>{{Cite book|last1=Bazhanov|first1=Y. V.|last2=Vlahko|first2=V. B.|editor1-first=Larry M|editor1-last=Stepp|editor2-first=Roberto|editor2-last=Gilmozzi|editor3-first=Helen J|editor3-last=Hall|title=Ground-based and Airborne Telescopes IV|date=2012-09-17|chapter=Design of an off-axis optical reflecting system|chapter-url=https://www.spiedigitallibrary.org/conference-proceedings-of-spie/8444/84446E/Design-of-an-off-axis-optical-reflecting-system/10.1117/12.926162.short?SSO=1|volume=8444|pages=84446E|doi=10.1117/12.926162|s2cid=119934177}}</ref> This involves various techniques including different types of equations for [[Ray tracing (physics)|ray-tracing]], and a goal can be optimizing the design.<ref>{{Cite book|last1=Bazhanov|first1=Y. V.|last2=Vlahko|first2=V. B.|editor1-first=Larry M|editor1-last=Stepp|editor2-first=Roberto|editor2-last=Gilmozzi|editor3-first=Helen J|editor3-last=Hall|title=Ground-based and Airborne Telescopes IV|date=2012-09-17|chapter=Design of an off-axis optical reflecting system|chapter-url=https://www.spiedigitallibrary.org/conference-proceedings-of-spie/8444/84446E/Design-of-an-off-axis-optical-reflecting-system/10.1117/12.926162.short?SSO=1|volume=8444|pages=84446E|doi=10.1117/12.926162|s2cid=119934177}}</ref>

An example of an off-axis optical system is a three mirror design as optics for a [[Hyperspectral imaging|hyperspectral imager]].<ref>{{Cite book|last1=Kim|first1=Youngsoo|last2=Hong|first2=Jinsuk|last3=Choi|first3=Byeongin|last4=Kim|first4=Yeonsoo|editor1-first=Miguel|editor1-last=Velez-Reyes|editor2-first=David W|editor2-last=Messinger|title=Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery XXIV|date=2018-05-08|chapter=Three mirror off-axis optical system with an obscuration hole as a fore optics of the hyperspectral imager|chapter-url=https://www.spiedigitallibrary.org/conference-proceedings-of-spie/10644/106441B/Three-mirror-off-axis-optical-system-with-an-obscuration-hole/10.1117/12.2284765.short|volume=10644|page=47|doi=10.1117/12.2284765|isbn=9781510617995|s2cid=125869107}}</ref>

==See also==
*[[Off-axis reflecting telescope]]

==References==
{{FS1037C}}
{{Reflist}}
[[Category:Geometrical optics]]


{{optics-stub}}